The present invention primarily is concerned with providing a solar heat collection and storage system which is closed and is provided with means to effectively deal with various conditions of the liquid which primarily is stored in a storage tank and which is also heated by one or more solar heat collecting units interconnected with said storage tank. On occasions, particularly when the system for heating the interior of a closed space, such as a dwelling or otherwise, does not lower the temperature of the liquid in the storage tank to such extent that it requires additional heating by the solar collecting units, said units, in the meantime, will be exposed to substantial solar heat. Under such conditions, liquid from the storage tank, upon passing to such heating solar heat collecting units, frequently is at least partially transformed into steam and said steam, together with heated liquid is circulated through the system and is transmitted back to the storage tank by appropriate conduits.
At least a few previous attempts have been made to transmit steam from solar heat collector units back to a storage tank, one such example being illustrated in U.S. Pat. No. 4,044,949 to Morawetz, dated Aug. 30, 1977. Said system is a so-called closed system and several examples of closed systems per se are illustrated in applicant's prior U.S. Pat. No. 2,342,211, dated Feb. 22, 1944, and his more recent U.S. Pat. No. 4,114,600, dated Sept. 19, 1978. In the latter patent, there is a disclosure of means to handle inert gas developed in the system and passed from the solar heat collectors to the storage tank but neither this patent nor the Morawetz patent include any means for specifically and effectively condensing steam or vapor developed in the system under the above-described circumstances and it is the principal purpose of the present invention to provide an effective means for condensing such steam or vapor and otherwise providing improvements over the systems found in said aforementioned patents, as well as other similar art.